Materials / Compare
Plastic PETG vs. Plastic UHMWPE
Compare Plastic PETG vs. Plastic UHMWPE strength, stiffness, weight and thermal properties.
| Try it on a partA bracket to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | 46.2MPasourcetypical | 20MPasourcetypical, tensile stress at yield ISO 527, 50 mm/min |
| Ultimate tensile strength | 46.2MPasourcetypical, peak stress (= stress at yield) | 43MPasourcetypical, tensile stress at break ISO 527, 50 mm/min |
| Flexural strength | 78.9MPasourcetypical | not sourced |
| Elongation at break | 7.6%sourcetypical | 465%sourcetypical, nominal elongation at break ISO 527 |
| Young's modulus (stiffness) | 1.94GPasourcetypical | 0.66GPasourcetypical, tensile modulus ISO 527, 1 mm/min |
| Density | 1,270kg/m³sourcetypical | 930kg/m³sourcetypical37% lighter |
| Strength to weight | 36.4kN·m/kg1.69x higher | 21.5kN·m/kg |
| Stiffness to weight | 1.53MN·m/kg2.15x higher | 0.71MN·m/kg |
| Poisson's ratio | not sourced | not sourced |
| Shear modulus | not sourced | not sourced |
| Bulk modulus | not sourced | not sourced |
| Speed of sound | 1,236m/s | 842m/s |
| Thermal | ||
| Thermal conductivity | 0.21W/m·Ksourcebase material: Eastman Eastar Copolyester 6763 (PETG), typical | 0.4W/m·Ksourcetypical, unfilled (narrative value, generic Celanese UHMWPE) |
| Thermal expansion | 51µm/m·Ksourcebase material: Eastman Eastar Copolyester 6763 (PETG), typical | 200µm/m·Ksourcetypical, 20 to 100 °C (generic Celanese UHMWPE) |
| 100 mm part over a 50 °C swing | 255µm growth3.92x less | 1,000µm growth |
| Specific heat | 1,300J/kg·Ksourcebase material: Eastman Eastar Copolyester 6763 (PETG), DSC at 60 °C (lowest temperature listed) | not sourced |
| Heats up and cools (diffusivity) | 0.127mm²/s | not sourced |
| Thermal shock resistance | not sourced | not sourced |
| Melting point | not sourced | 130–138°CsourceDSC 10 K/min |
| Glass transition | 77.4°Csourcetypical | not sourced |
| Max service temperature | 76.2°CsourceHDT 0.455 MPa (printed specimens) | 80°Csourcerecommended max constant operating temperature |
| Values for | Ultimaker PETG, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS v1.00, April 29, 2022. | Celanese GUR 4120 (avg. molecular weight 4.7x10^6 g/mol), typical values on compression-molded specimens; CTE and thermal conductivity from Celanese's generic UHMWPE guide (grade not named) |
Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Plastic PETG is 3D printed: its properties depend on build direction and print settings; these are typical values.
Questions
Is Plastic PETG stronger than Plastic UHMWPE?
Plastic PETG is stronger: its yield strength is 46.2 MPa against 20 MPa for Plastic UHMWPE (2.31x).
Which is lighter, Plastic PETG or Plastic UHMWPE?
Plastic UHMWPE is lighter: 930 kg/m³ against 1,270 kg/m³ for Plastic PETG.
Which is stiffer, Plastic PETG or Plastic UHMWPE?
Plastic PETG is stiffer: Young's modulus 1.94 GPa against 0.66 GPa for Plastic UHMWPE, so the same part in Plastic PETG deflects less under the same load.
Which is lighter for the same job, Plastic PETG or Plastic UHMWPE?
For the same stiffness or strength: Plastic PETG is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Plastic PETG | Plastic UHMWPE |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 2.15x heavier |
| Stiff beam (bending) | lighter | 26% heavier |
| Stiff panel or plate | lighter | 5% heavier |
| Strong rod or tie | lighter | 1.69x heavier |
| Strong beam | lighter | 28% heavier |
| Strong panel or plate | lighter | 11% heavier |
For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).
Which conducts heat better, Plastic PETG or Plastic UHMWPE?
Plastic UHMWPE conducts heat better: 0.4 W/m·K against 0.21 W/m·K for Plastic PETG.
Which expands less with temperature?
Plastic PETG expands less: 51 µm/m·K against 200 µm/m·K for Plastic UHMWPE.